Publications by authors named "Meirav Avital-Shacham"
Article Synopsis
- The study focuses on understanding how regulators of G protein signaling (RGS) proteins accelerate GTPase activity and their specificity in interacting with G proteins.
- Researchers conducted biochemical assays to identify key residues in RGS domains that enhance or decrease their interaction with Gα subunits.
- Findings indicate that certain conserved RGS residues interact with crucial parts of Gα, and the balance between beneficial and detrimental interactions determines the effectiveness of RGS proteins.
Article Synopsis
- RGS6 and RGS7 are proteins that regulate G protein signaling by inactivating G proteins, playing key roles in various biological processes, particularly in the heart and nervous system.
- The study identifies specific residues in RGS6 and RGS7 that allow these proteins to distinguish between closely related Gα subunits, revealing a sophisticated system that balances both inhibitory and modulatory effects on signaling.
- These findings enhance the understanding of how RGS6 and RGS7 achieve their specificity in protein interactions, highlighting the importance of their RGS domains in determining how they function with Gα subunits.
Structural motifs in the RGS RZ subfamily combine to attenuate interactions with Gα subunits.
Biochem Biophys Res Commun
September 2018
Regulators of G-protein Signaling (RGS) proteins inactivate heterotrimeric G proteins, thereby setting the duration of active signaling. In particular, the RGS RZ subfamily, which consists of RGS17, RGS19, and RGS20, mediates numerous physiological functions and human pathologies - mostly by functioning as GTPase Activating Proteins (GAPs) towards the Gα subfamily. Yet, which RZ subfamily members mediate particular functions and how their GAP activity and specificity are governed at the amino acid level is not well understood.
View Article and Find Full Text PDFArticle Synopsis
- RGS proteins, like RGS2, inactivate Gα subunits and regulate G protein-coupled signaling networks, with RGS2 exclusively interacting with Gα subunits.
- Research reveals that three specific residues in RGS2 influence its unique interaction mode with Gα, primarily via the Gα GTPase domain.
- The study identifies key residues in the Gα helical domain as crucial for RGS2 specificity, offering insights into G protein interactions that could aid in designing new drugs and understanding signaling pathways.
Article Synopsis
- * RGS proteins, particularly from the R12 subfamily, show lower activity in regulating G proteins compared to the R4 subfamily, where we've identified key "disruptor residues" affecting this activity.
- * By engineering RGS proteins with and without these disruptor residues, we found that altering these positions can significantly change the activity levels toward Gα proteins, indicating they play a crucial role in regulating G protein signaling.
Unlabelled: The adenovirus E4orf4 protein induces nonclassical apoptosis in mammalian cells through at least two complementing pathways regulated by the interactions of E4orf4 with protein phosphatase 2A (PP2A) and Src kinases. In Saccharomyces cerevisiae cells, which do not express Src, E4orf4 induces PP2A-dependent toxicity. The yeast Golgi apyrase Ynd1 was found to contribute to E4orf4-mediated toxicity and to interact with the PP2A-B55α regulatory subunit.
View Article and Find Full Text PDFBackground: The adenovirus E4orf4 protein must bind protein phosphatase 2A (PP2A) for its functions.
Results: The E4orf4 binding site in PP2A was mapped to the α1,α2 helices of the B55α subunit.
Conclusion: The E4orf4 binding site in PP2A-B55α lies above the substrate binding site and does not overlap it.